How to make the chacter detect stairs and react to it
It sounds like you need to change the action mode to play, and you might have it set to "loop stop" or "loop end".



Here is a list of the play-modes for your benefit.


PLAY- plays the action once on a positive pulse.
PING-PONG- plays the animation forward and backward
FLIPPER- plays the animation first forward, then after a negative pulse plays it backward.
LOOP-STOP- will play the animation over and over as long as it has a positive pulse.
LOOP-END- Like loop stop, but even after positive pulse is gone, it will finish playing the animation cycle it is in.
PROPERTY- plays the animation based on a value from an existing game property.